Why is it wrong to say “that tree is falling tomorrow”?

Why is it wrong to say:

That tree is falling tomorrow

The answer key says, in common, it is right to use -ing with near future. But it says that sentence is wrong, because it doesn’t show the specific near future. However there is “tomorrow”! Why is that wrong?

Solution 1:

Because the use of present tense forms with future meaning nearly always has an implication of intention, or at least of being scheduled.

You can say

That tree is being felled tomorrow.

because that implies that somebody is intending to fell it.

But trees falling are not generally intentional acts.